Thanks for taking the time to post your question in our Community! =)
With all the awesome Apps available these days I can see why you'd want to ability to download more Apps or even design your own for the SHM Touchpad. While I too wish this was an option, all the programming, firmware updates and Apps are designed by the vendor that provides us with the software. There is no option to sideload applications to the Touchpad.
If you have some suggestions for App's you'd like to see on the Touchpad in the future feel free to post them here and we can pass it along to the Product team to review.